Very bad experience!!!!

I purchased a Mercedes on finance about a year ago from black horse. Everything was fine up until the vehicle started to have problems. My vehicle would not move due to a electronic fault and black horse said they will send an engineer to asses it. They took so long to send an engineer that before he could arrive someone smashed in to the back of my car and drove off so I had to claim through my insurance and pay the excess so I now have a fault claim on my name and still had to pay my loan back every month. Black horse said "when you get the vehicle back let us know and we will send an engineer immediately". Black horse then sent an engineer after a week of me telling them I now have my vehicle. Black horse now say in normal cases it can take 56 days to reach a conclusion when we have the engineers report. Absolutely dreadful as I have to still pay for my car every month but have no car to drive and also can not get to work using my car which is 40 miles away so have to hire a car or use public transport that takes 2 hours. AVOID THIS COMPANY AS THEY WILL NOT HELP IN ANY CIRCUMSTANCE!!